In Defense of Women is H. L. Mencken's 1918 book on women and the relationship between the sexes. Some laud the book as progressive while others brand it as reactionary. While Mencken didn't champion women's rights, he described women as wiser in many novel and observable ways, while demeaning average men.

According to Mencken's biographer, Fred Hobson:

"Depending on the position of the reader, he was either a great defender of women's rights or, as a critic labelled him in 1916, 'the greatest misogynist since Schopenhauer','the country's high-priest of woman-haters.'"